Farm and product carbon footprints of China's fruit production--life cycle inventory of representative orchards of five major fruits.

Understanding the environmental impacts of fruit production will provide fundamental information for policy making of fruit consumption and marketing. This study aims to characterize the carbon footprints of China's fruit production and to figure out the key greenhouse gas emissions to cut with improved orchard management. Yearly input data of materials and energy in a full life cycle from material production to fruit harvest were obtained via field visits to orchards of five typical fruit types from selected areas of China. Carbon footprint (CF) was assessed with quantifying the greenhouse gas emissions associated with the individual inputs. Farm and product CFs were respectively predicted in terms of land use and of fresh fruit yield. Additionally, product CFs scaled by fruit nutrition value (vitamin C (Vc) content) and by the economic benefit from fruit production were also evaluated. The estimated farm CF ranged from 2.9 to 12.8 t CO2-eq ha(-1) across the surveyed orchards, whereas the product CF ranged from 0.07 to 0.7 kg CO2-eq kg(-1) fruit. While the mean product CFs of orange and pear were significantly lower than those of apple, banana, and peach, the nutrition-scaled CF of orange (0.5 kg CO2-eq g(-1) Vc on average) was significantly lower than others (3.0-5.9 kg CO2-eq g(-1) Vc). The income-scaled CF of orange and pear (1.20 and 1.01 kg CO2-eq USD(-1), respectively) was higher than apple, banana, and peach (0.87~0.39 kg CO2-eq USD(-1)). Among the inputs, synthetic nitrogen fertilizer contributed by over 50 % to the total greenhouse gas (GHG) emissions, varying among the fruit types. There were some tradeoffs in product CFs between fruit nutrition value and fruit growers' income. Low carbon production and consumption policy and marketing mechanism should be developed to cut down carbon emissions from fruit production sector, with balancing the nutrition value, producer's income, and climate change mitigation.